Filters (GSO)

[OzStarGazer]

Is there a huge difference between a polarising filter and a neutral density filter? I was thinking of buying both as they are relatively cheap, but I don't really want to waste money if they are similar.
I have read that the polarising filter is for daytime viewing. And that both reduce glare? Plus two polarising filters can be combined to create a variable polarising filter? So maybe buying two polarising filter is the best option?
PS: I already have a Celestron LPR/UHC filter as well as some colour filters.

Thanks!

[cometcatcher (Kevin)]

A neutral density filter makes everything darker (light at all angles). That is it's only function. A polarising filter makes light darker that hits it from an angle but lets direct light through, much like polarising sunglasses if you've ever used those.

See here. http://en.wikipedia.org/wiki/Polariz...photography%29

[OzStarGazer]

Thanks, Kevin!

[OzStarGazer]

I think the polarizing filter is better for me. I am only not sure if I should buy one or two - because ultimately I could also combine a polarizing filter with a grey filter for example (which I already have). I only have a 5" scope so it does let in light, but it is not a huge scope...

[glend (Glen)]

Where do you live? You might be better off spending your money on a light pollution reduction filter.

[OzStarGazer]

Thanks, I already have one.
I wanted to use the polarizing one mainly for daytime viewing. I did try the LPR filter during the day and it was better than nothing, but not really good.

[glend (Glen)]

Ah I see getting setup for the datime occulation of Saturn by the Moon on the 22nd.

[OzStarGazer]

Yes, hopefully I can see it with my 5" telescope! I can see Saturn quite clearly in the morning, but during the day... even with a filter... I really don't know. Anyway,there is another occultation on the 14th of May in the evening.

I think I will only buy one for the moment and if I need more darkness I will combine it with the grey filter.